Disconnecting contact



Sept. 2, 1941. H. H. RUG'G DISCONNECTING CONTACT Filed Sept. 9, i939 INVENTOR flora/0V7. 16 1/99? WITNESSES:

AOEY

Patented as. a, 1941 iorrlc mscomcrmo coarser Harold H. Bug, Forest Hills, Ea -E Electric & a Pittsburgh, Pa, a corporation Westinghouse Deny, East Pennsylvania Application September 9, 1939, fierlal no. 294,039

9 Claims. =(ci. ace-res) as, for example, on removable truck-type circuit breakers and in metal clad switchsear.

An object of my invention, generally stated, is to provide a disconnecting contact which shall invention relates; generally, to electric be simple and emcient in operation and which vide a disconnecting contact having suficient.

flexibility to permit some misalignment between the connected members.

Fla. 5 is a plan view of the base for supporting the contact fingers.

Referring to the drawing. the switch structure shown therein comprises a base member it having a cylindrical recess II therein, a plurality of contact fingers l2 having one end disposed to engage a rectangular conductor or switch blade to and the other end disposed in. the recess H, and a plurality of'sprlnss l4 to bias the contact fingers It toward each other and into encasement with the conductor l3.

As shown, the base member it is of a rectangular shape and may be composed of copper or other suitable conducting material. The groove or recess ii provided in the base it is preferably 01 a cylindrical shape in order to facilitate ma-= chinins and n provided with an owning it; at one side of the base member. A pair of conduct ins members it may be'secured in rectangular groova ll provided-in another side of the base member it. The conducting members it. may be connectm to'bmbars or other suitable current conductors (not shown) n show in Fig. 3, each one (lithe contact Other objects of my invention will be explained g5 fingers i2 is provided with a rounded end or hub fully hereinafter or will be apparent to thwe skilled in the art.

According to one embodiment oi, my invmflon, a plurality of pairs of oppositely contact fingers are so mounted in a contact base that one end of each-finger is forced into enc sement portion it, which is otasmaller diameter than c vlded with a rounded surface it for engaging with the base when the opposite and engages a co operating blade or conducting member. Suficient clearance is provided between the contact fingers and the base to allow mlssilsnmentbetween the base and the switch blade. fish contact pressure between the fingers, which engage the blade on opposite sides, and the blade and also between the fingers and the base-member is connect the lingers in groups with two pairs of fingers in each group.

shown in Fig. i;

, Fig. 3 is a plan view of one o! the contact fin gers utilized in the switch structure;

= Fi i is a view in elevation of the contact on ger shown in Fig. 3, and

$5 contact finger is ofiset slightly from the blade portion in order that the fingers may be assembled in the base member it in oppositely dis posed pairs, with the-blades of the fingers in alignment, as shown in Figs. 1 and 2. In this maintained by springs pmvmed bolts which manner, the fingers are prevented from co1laps= 45 moved from the blade it.

The contact fingers It may be assembled in the base it by inserting the rounded portions loin the recess ll through the ends oi the base It. As

previously stated. the fingers are assembled in opso positely disposed pairs and they may be held in place by a bolt '22 which is inserted through a 1 cylindrical opening 33 provided in the hub or each finger. The pairs of dimers may be spaced from each other by washers fill disposed on the bolt 23.

and end washers may be utilized to close the fingers are properly assembled.

In order that the rounded portions l8 of the fingersmay move outwardly into engagement with the base member l when the blade I3 is forced between the contact fingers, the hole 23 is of a larger diameter than the bolt 22. In this manner the outer surface of the hub I8 of each finger is forced into engagement with the rounded surface of the base 10, as shownin Fig. 1, thereby insuring good electrical contact between the contact fingers and the base I 0 when the fingers are in engagement with the conductor l3.

As shown in Figs. 1 and 2, the fingers are connected in groups, with two pairs of fingers in each group, and a comparatively heavy contact pressure is applied at the contact points by means of the springs II which are mounted on bolts 26. Crimp washers 21 are provided for engaging the upper and the lower contact fingers of the group connected by each one of the bolts 26. As shown in Fig. 2,'the: springs H are disposed between the lower crimp washers 21 and the heads of the bolts 26. In this manner one bolt and one spring serves to compress two pairs of contact fingers.

The opening I 5 for the recess H in the base l0 through which the fingers project is shaped so that they are held in nearly their normal position where they will properly engage the blade l3. However, some misalignment between the blade l3 and the base I0 is permissible since the opening [5 is slightly larger than the space required for the blades of the contact fingers when assembled in pairs, and the diameter of the recess II is also slightly larger than the diameter of the portion l8 of the fingers.

It will be noted that the fingers cannot come openings at the end of the recess ll after the opening to said recessand substantially less than the diameter of the recess, and means for retaining said fingers in said recess.

2. A disconnecting contact comprising a base member having a cylindrical recess therein, a plurality of contact fingers having a rounded hub portion movably disposed in said recess, the diameter of said hub portion being greater than the width of the opening to said recess and substantially less than the diameter 'of the recess, resilient means for biasing said contact fingers in opposite directions, andmeans for retaining said fingers in said recess.

3. A disconnecting contact comprising a base member having a .cylindrical recess therein, a plurality of oppositely disposed contact fingers having a rounded hub portion movably mounted in said recess, the diameter of said hub portion being'greater than the width of the opening to said recess and substantially less than the diameter of the recess, and resilient means for biasing'said contact fingers toward each other.

4. A disconnecting contact'comprising a base member having a cylindrical recess therein, a plurality of pairs of oppositely disposedv contact fingers'having a rounded end movably mounted in said recess, the diameter of said end being out through the opening l5 and that they are not held rigidly in place by the bolt 22. This bolt merely functions to retain the end washers 25 in place to prevent the fingers from coming out through the ends of the base member l0. Furthermore, as explained hereinbefore, the fingers are prevented from collapsing by the engaging surfaces 2| on the blades of the fingers when withdrawn from the blade l3.

From the foregoing description it is apparent that I have provided a disconnecting contact suitable for disconnecting conducting members,

which has a relatively high current carrying capacity since the-current is conducted directly through the switch'members without the use of flexible shunts. Furthermore, the contact pressure between the conducting members may be readily adjusted by varying the compression of the springs II and any desired number of contact fingers may be easily provided, thereby increasing or decreasing the capacity of the switch as desired. The present switch is particularly suitable for use with rectangular shaped conductors or bus bars having high current carrying capacity.

I do not desire to be restricted to the particular form or arrangement of parts herein shown and described since it is evident that they may be changed and modified without departing from the spirit and scope of my invention as defined in the appended claims.

I claim as my invention:

1. A disconnecting contact comprising a base member having a cylindrical recess therein, a

plurality of contact fingers having a rounded end movably disposed in said recess. the diameter of said end being greater than the width of t e greater than the width of the opening to said recess and substantially less than the diameter of the recess, resilient means for biasing each pair of fingers toward each other, and means for retaining said fingers in said recess.

5. A disconnecting contact comprising a base I member having a cylindrical recess therein, a plurality of pairs of oppositely disposed contact fingers having a rounded end movably mounted in said recess, the diameter of said end being greater than the widthof the opening to said recess and substantially less than the diameter ofthe recess, resilient means for biasing each pair of fingers toward each other, means for retaining said fingers in said recess, and means on said fingers for limiting their. travel toward each other.

6. A disconnecting contact comprising a base member having a cylindrical recess therein, a plurality of pairs of oppositely disposed contact fingers, each one of said fingers having a rounded end movably mounted in said recess, the diameter of said end being greater than the width of the opening to said recess and substantially less than the diameter of the recess, means for retaining said fingers in said recess, and resilient means for biasing the fingers of each pair toward each other.

7. A disconnecting contact comprising a base member having a cylindrical recess therein, a plurality of pairs of oppositely disposed contact fingers, each one of said fingers having a rounded end movably mounted in said recess,-each finger having a hole through its rounded end, a bolt passing through said holes to retain the fingers in said recess, the-diameter of said bolt being less than the diameter of the holes in the fingers to permit the fingers to be moved outwardly into engagement with said base, and resilient means for biasing the fingers of each pair toward each other.

8. A disconnecting contact comprising a base member having a cylindrical recess therein, a plurality of pairs of oppositely disposed contact fingers having one end movably mounted in said recess, said end being rounded and of a greater diameter than the width of the opening to said recess, means for retainingsaid fingers in said recess, said end being rounded and of a Bree-teri0 diameter than the width of the opening to said recess, means for retaining said'nngers in Said recess, resilient means for biasing the ends 0! said fingers in opposite directions into engagement with said base, and means for adjusting said resilientmeans to vary the contact pressure between the fingersand the base the diameter of said rounded ends'being substantially less than the diameter of said recess.

HAROLD H. RUGCt. 

